2-amino-5-hydrocarbyldithio-1,3,4-thiadiazole and compositions thereof

ABSTRACT

SEQUENTIALLY WITH AN ALKALI METAL HYDROXIDE AND A HYDROCARBYL SULFENYL BROMIDE CHARACTERIZED BY THE FORMULA R-S-Br where R and R&#39;&#39; are as heretofore defined. Hydrocarbon oil compositions comprising a hydrocarbon oil of lubricating viscosity containing between about 0.01 and 50 wt. percent of said amino hydrocarbyldithio thiadiazole.   WHERE R is hydrocarbyl of from 1 to 30 carbons and R&#39;&#39; is hydrogen or hydrocarbyl of from 1 to 30 carbons prepared by the method of contacting a 2-amino-5-mercapto-1,3,4-thiadiazole characterized by the formula:   Thiadiazole derivatives characterized by the formula:

States Patent 1191 Waldbillig 1111 3,869,395 [451 Mar.4, 19752-AMINO-S-HYDROCARBYLDITHIO-l,3,4-

THIADIAZOLE AND COMPOSITIONS THEREOF [75] inventor: James O. Waldbillig,Wappingers Falls, NY.

[73] Assignee: Texaco Inc., New York, NY.

[22] Filed: Feb. 25, 1974 [21] Appl. No.: 445,384

Primary Examiner-W. Cannon Attorney, Agent, or Firm-T. H. Whaley; C. G.R165 [57] ABSTRACT Thiadiazole derivatives characterized by the formula:

where R is hydrocarbyl of from 1 to 30 carbons and R is hydrogen orhydrocarbyl of from 1 to 30 carbons prepared by the method of contactinga 2-amino-5- mercapto-l,3,4-thiadiazole characterized by the formula:

sequentially with an alkali metal hydroxide and a hydrocarbyl sulfenylbromide characterized by the formula R-S-Br where R and R are asheretofore defined. Hydrocarbon oil compositions comprising ahydrocarbon oil of lubricating viscosity containing between about 0.01and 50 wt. percent of said amino hydrocarbyldithio thiadiazole.

9 Claims, N0 Drawings 2-AMIljgkS-HYDROCARBYLDITHIO-1 ,3,4- THIADIAZOLEAND COMPOSITIONS THEREOF BACKGROUND OF INVENTION In the internalcombustion engines of today as well as mechanisms associated therewithsuch an automatic transmissions, a substantial amount of copper isemployed in the construction thereof. However, some of the most commonlyused additives in lubricating oil compositions servicing the internalcombustion systems, e.g., gear oils, are highly corrosive to copper.Specifically, among the most effective agents which have been developedfor compounding with lubricants to improved extreme pressure and wearproperties are sulfur containing organic compounds, for example,sulfurized triisobutylene and sulfurized diisobutylene, sulfurizedterpene, sulfurized hydrocarbon oils, vegetable oils, animal oils,xanthate esters, organic polysulfides, particularly polyalkylpolysulfides which contain sulfur or sulfur compounds. These wear andextreme pressure agents are corrosive to copper. In addition, thosehydrocarbon oils derived from high sulfur containing crude oils whereinthe sulfurous components are not thoroughly removed in refining areoften corrosive to copper.

To solve this problem of copper corrosion, the prior art employs variouscopper corrosion inhibitors with varying degree of effectiveness. Onesuch class of inhibitors are disclosed in U.S. Pat. Nos. 2,719,125 and2,719,126 which are directed to copper corrosion inhibited lubricatingoil compositions containing as the copper coro s ion inhibitor a1,3,4-thiadiazole polysulfide characterized by the formula:

E Ii -(S) Ps- SUMMARY OF INVENTION 1 have discovered and thisconstitutes one aspect of my invention a new class of sulfur compoundswhich are effective in inhibiting the corrosion of copper by coppercorrosive hydrocarbon oil formulations. Another aspect of my inventionare hydrocarbon oil formulations containing the novel sulfur compounds.More particularly, the instant invention relates to a 2-amino-S-hydrocarbyldithio-1,3,4-thiadiazole characterized by theformula:

NN R set Ii s-s-R where R is hydrocarbyl of from 1 to 30 carbons and Rishydrogen or hydrocarbyl of from 1 to 30 carbons. In

addition, the invention specifically relates to concotrate and finishedhydrocarbon oil composition comprising a hydrocarbon oil of lubricatingviscosity and said amino hydrocarbyldithio thiadiazole.

DETAILED DESCRIPTION OF THE INVENTION Specifically, the aminohydrocarbyldithio thiadiazole compounds of the invention are prepared byfirst reacting thiosemicarbazide of the formula:

where R is as heretofore defined. The reaction is carried out at atemperature between about 20 and 200C. utilizing a mole ratio of thethiosemicarbazide to carbon disulfide of between about 1:10 and 4:1.Further description of the 2-amino-5-mercapto-1,3,4- thiadiazole productcan be found in US. Pat. No. 2,389,126.

The formed 2-amino-5-mercapto-l ,3;4-thiadiazole is then contacted withan alkali metal hydroxide such as sodium hydroxide and potassiumhydroxide at a temperature between about 20 and 100C. utilizing a moleratio of thiadiazole to alkali metal hydroxide of between about 2:1 and1:1.1 to form the alkali metal mercaptide intermediate characterized bythe formula:

l H S where M is the alkali metal moiety and R is as hereto foredefined.

The intermediate mercaptide salt is contacted with a hydrocarbylsulfenyl bromide characterized by the formula R-S-Br where R ishydrocarbyl, i.e., alkyl, aryl, alkaryl or aralkyl of from 1 to 30carbons. The reaction is conducted at a temperature between about 50 and50C. utilizing a mole ratio of thiadiazole reactant to hydrocarbylsulfenyl bromide of between about 1.1:! and 111.1. The sulfenyl bromidereactant is prepared by reacting hydrocarbyl mercaptan e.g. alkylmercaptan with bromine at temperatures between about -50 and 50C.utilizing a mole ratio of mercaptan to bromine of between about 2:1 and1:20.

In the foregoing described reactions, liquid diluents are advantageouslyemployed, e.g., in amounts of between about 25 and wt. percent of thereaction mixtures. Examples of such diluents are benzenedimethylformamide, mixtures of benzene and dimethylformamide, toluene o,m-, and p-xylene and mixtures thereof, N,N-diethylformamide,' N,N-dimethylacetamide, diglyme (diethylene glycol dimethyl ether),chlorobenzene, carbon tetrachloride, hexachloroethane, ethylene glycoldimethyl ether. In

most instances a single solvent will not be suitable for all stages thusnormally requiring the use of several different solvents.

All stages of the reaction are preferably conducted in an inertatmosphere such as nitrogen.

Examples of the thiosemicarbazide reactants contemplated herein arethiosemicarbazide, 4-ethyl-3- thiosemicarbazine,4-propyl-3-thiosemicarbazide, 4-butyl-3-thiosemicarbazide, 4-pentyl-3-thiosemicarbazide, 4-heXyl-3-thiosemicarbazide,4-heptyl-3-thiosemicarbazide, 4( Z-ethylhexyl )-3- thiosemicarbazide,4-tert-octyl-3-thiosemicarbazide, 4-dodecyl-3-thiosemicarbazide,4-tetradecyl-3- thiosemicarbazide, and 4-octadecyl-3- thiosemicarbazide,4-methyl-3-thiosemicarbazide, 4-phenyl-3-thiosemicarbazide, 4-benzyl-3-thiosemicarbazide, 4-tolyl-3-thiosemicarbazide, 4-

naphtyl-3-thiosemicarbazide.

Examples of the amino mercapto thiadazoles contemplated herein are whereR and Z are hydrogen where R is ethyl and Z is hydrogen; where R ishydrogen and Z is potassium; where R is ethyl and Z is potassium; whereR is hydrogen and Z is sodium, where R is methyl and Z is potassium;where R is tert-octyl and Z is potassium; where R is dodecyl and Z issodium; where R is octadecyl and Z is sodium; where R is tolyl and Z ispotassium; where R is phenyl and Z is sodium; where R is naphthyl and Zis potassium and where R is benzyl and Z is sodium.

Examples of the hydrocarbyl sulfenyl reactants are -t-dodecyl sulfenylbromide, t-octyl sulfenyl bromide,

Z-methyl-Z-butyl sulfenyl bromide, 3-methyl-l-butyl sulfenyl bromide,n-pentyl sulfenyl bromide, n-octyl sulfenyl bromide, n-dodecyl sulfenylbromide, noctadecyl sulfenyl bromide, tolyl sulfenyl bromide, naphthylsulfenyl bromide, phenyl sulfenyl bromide and benzyl sulfenyl bromide.

Examples of the amino hydrocarbyldithio thiadiazole productscontemplated herein are 2-amino-5-tdodecyldithiol ,3,4-thiadiazole;Z-ethylamino-S-toctyldithio-l ,3,4- thiadiazole;2-amino-5-t-octyldithio- 1,3,4-thiadiazole; 2amino-5-n-octadecyldithio-l,3,4- thiadiazole; Z-ethylamino-S-n-octadecyldithio-l,3,4- thiadiazole;2-(2-ethylhexyl)amino-5-n-dodecyldithio- 1,3,4-thiadiazole; 2-(2-ethylhexyl)amino-5-noctyldithio-l ,3,4-thiadiazole;2naphthyl-5-octyldithio- 1,2,3-thiadiazole; 2-benzyl-5-pentyldithio-l ,3,4- thiadiazole; 2-amino-5-phenyldithio-l,3,4-thiadiazole and2-amino-5-tolyldithio-1,3,4-thiadiazole.

In regard to the finished compositions of the present invention, theamino hydrocarbyldithio thiadiazole products are employed in hydrocarbonbase oil in copper corrosion inhibiting amounts, e.g., from betweenabout 0.01 and wt. percent, preferably between about 0.05 and 1 wt.percent. The hydrocarbon base oil in the finished composition normallyconstitutes at least about 85 wt. percent of said composition,preferably about 90 wt. percent or more. Hereinbefore and hereinafter bythe term finished" it is intended to denote that the composition is in astate ready for ultimate use without need for further dilution with baseoil.

In the concentrate compositions contemplated to which additionalhydrocarbon oil is added to form the finished compositions, theconcentrate form bcing preferably for storage and transport, thehydrocarbon base oil normally constitutes at least about 50 wt. percent,preferably between about 50 and wt. percent and the aminohydrocarbyldithio thiadiazole between about 10 and 50 wt. percent of theconcentrate formulation.

Thus, concentrate and finished compositions are contemplated rangingfrom at least about 50 wt. percent hydrocarbon oil and between about0.01 and 50 wt. percent amino hydrocarbyldithio thadiazole additive.

The hydrocarbon oil components employed in the finished and concentrateformulations of the invention advantageously are mineral lubricatingoils such as paraffinic lube oil, naphthenic lube oil and mixturesthereof. Other suitable hydrocarbon oils are those synthetically formedsuch as the polyalkylene, e.g., polyisobutylene of a molecular weight offrom about 1,000 to 5,000. The viscosity of the base oils employed willbe dependent upon the particular use intended for the finishedformulation. However, the viscosity of oil employed will generally rangebetween about 70 and 5,000 SUS at F.

In addition to the hydrocarbon oil and amino hydrocarbyldithiothiadiazole components in the contemplated oil compositions, otheradditives are normally employed, the particular other additives utilizedbeing dependent on the specific service intended for the finishedcompositions of the invention. Some of the other additives contemplatedbelong in classes of detergentdispersants, pour depressants, VIimprovers, extreme pressure agents, antiwear agents, antioxidants,supplementary corrosion inhibitors and antifoamants.

Examples of the extreme pressure and antiwear agents are dithiolethionederived from sulfuriziing triisobutylene and alkyl sulfides, disulfidesand polysulfides prepared by sulfurization of isobutylene with sulfurdichloride. Other extreme pressure and antiwear agents contemplated arethe sulfurized terpenes, sulfurized hydrocarbon oils and polyalkylpolysulfldes, all of which contain active sulfur or sulfur compoundswhich are corrosive to copper. These extreme pressure and antiwearagents are normally present in the finished formulations (when utilized)in amounts of between about 0.1 and 10 wt. percent, preferably between0.5 and 5 wt. percent.

When detergent-dispersants are employed, they are usually utilized inamounts between about 0.5 and 5 wt. percent. Examples of ashlessdispersants are alkenyl succinimides characterized by the generalformula:

ene, tetramine, tetraethylene pentamine derivatives of polyisobutylenesuccinic anhydride, particularly where R is of a molecular weightbetween about 700 and 2,000, e.g., about 1,300. These ashlessdispersants are further described in U.S. Pat. Nos. 3,172,892 and3,202,678. The non ashless dispersants which may be utilized are thealkaline earth metal overbased calcium alkaryl sulfonates such ascalcium carbonate overbased calcium alkaryl sulfonate wherein thealkaryl sulfonate moiety is of a molecular weight of 500 to 1,000. Theseoverbased sulfonates are further described in U.S. Pat. Nos. 3,027,325,3,312,618 and 3,537,996.

Examples of the contemplated viscosity index improvers which in manyinstances also function as pour depressors are the methacrylate esterpolymers characterized by the general formula:

where R is an alkyl group, a dimethylamino group or mixtures of saidgroup containing from 1 to 20 carbons and y is an integer providing amolecular weight of the polymer in the range of 25,000 to1,250,000,preferably 50,000 to 500,000. Methacrylate ester polymers possessingpour point depressant as well as viscosity index improving propertiesare well known, e.g., U.S. Pat. No. 2,737,496. A very effective materialof this type is the tetrapolymer of butyl, lauryl, stearyl anddimethylaminoethyl methacrylate in approximate ratios of 1:2:1:0.2. Themethacrylate ester is advantageously employed in the base oils inamounts ranging from 0.1 to wt. percent, preferably about 0.2 to 5 wt.percent, in order to impart the desired viscosity index and/or pourpoint thereto.

Examples of suitable antioxidants which also function as supplementarycorrosion inhibitors are the aryl substituted amine compoundsexemplified by phenylnaphthylamine as well as compounds such asphenylenediamine, phenathiazine, diphenylamines employed in amountsbetween about 0.1 and 5 wt. percent. Some of the preferred compounds arethe phenylalphanaphthylamines and a mixture of 2,2-diethyl-4,4'-t-dioctyldiphenyleneamine and 2,2'-diethyl-4,6- diphenylamine.

Additional examples of antioxidants are the hydrocarbyldithiophosphates. Particularly effective compound in this class are zincdi(nonylphenoxyethyl) dithiophosphate, zinc di(dodecylphenoxyethyl)dithiophosphate and zinc di(nonylphenoxyethoxyethyl) dithiophosphateprepared by reacting nonyl phenol and ethylene oxide compounds withphosphorus pentasultide followed by neutralization of the acid formedwith basic zinc compound such as zinc carbonate, zinc oxide or zinchydroxide. The general preparation and description of the compounds inthis class are disclosed in U.S. Pat. Nos. 2,344,395 and 3,293,181.

Examples of additional supplemental corrosion inhibitors are oleyl amineand ethyloleyl acid phosphate.

Antifoamants which are suitable for use are the sililcone polymers suchas polymeric dimethyl silicone.

The following examples further illustrate the invention but are not tobe construed as limitations thereof.

EXAMPLE I This example illustrates the preparation of -2-amino-S-mercapto-l ,3,4-thiadiazole reactant.

To a solution of 45.5 grams (0.5 mole) of thiosemicarbazide in 1,000mls. of dimethylformamide there was charged 32 grams of carbondisulfide. The resultant solution was heated for 4 hours at C. and thenstripped to 93C. under reduced pressure of 0.15 mm Hg. The residue wasslurried. with 250 mls. of benzene followed by removal of the benzenevia distillation. The residue product was recrystallized from 250 mls.of methanol-ethanol mixture (Formula 30) to yield 28 grams (42 wt.percent) of product which was analyzed and found to be2-amino-5-mercapto-l,3,4- thiadiazole having an elemental analysis of31.7 (calc. 31.6) wt. percent nitrogen; 47.1 (48.1) wt. percent sulfur;19.2 (18.0) wt. percent carbon and 2.1 (2.3) wt. percent hydrogen.

EXAMPLE ill This example illustrates the preparation of 2-ethylamino-5-mercapto-l ,3,4-thiadiazole reactant.

To a stirred solution of 11.9 grams (0.10 mole) of4-ethyl-3-thiosemicarbazide and 700 mls. of dimethylformamide there werecharged 8.4 grams (0.1 l of carbon disulfide. The reaction mixture washeated at C. for 4 hours and stripped to 93C. under reduced pressure of0.04 mm Hg. The residual solid was recrystallized from absolute ethanoland analysis found it to be 2-ethylamino-5-mercapto-1,3,4-tlhiadiazoleof an elemental analysis of 29.5 (calc. 29.8) wt. percent carbon; 4.7(4.4) wt. percent hydrogen; 2.5.6 (26.1) wt. percent nitrogen and 39.4(39.7) wt. percent sulfur.

EXAMPLE III This example illustrates the preparation of a species of theproduct of the invention from a product of the type formed in Example I.

A solution of 5.6 grams (0.] mole) of potassium hydroxide and 50 mls. ofethanol was added to a mixture of 13.3 grams (0.10mole) of2-amino-5-mercapto- 1,3,4-thiadiazole in 200 mls. of diglyme (diethyleneglycol dimethyl ether) at 0C. There was added mls. of benzene and theresultant mixture was heated to 49C. on the rotary evaporator to removebenezene and ethanol leaving the potassium salt of 2-amino-5-mercapto-1,3,4-thiadiazole as residue.

A t dodecyl sulfenyl bromide solution was prepared by adding 16 grams(0.10 mole) of bromine to a solution of 100 mls. of carbon tetrachlorideand 20.2 grams (0.10 mole) t-dodecyl mercaptan at a temperature of about0C. The product was blown with nitrogen for a period of 2 hours.

The formed t-dodecyl sulfenyl bromide solution was added to the aboveformed potassium salt. The resultant product was stripped to 93C. (0.15mm Hg), dissolved in 300 mls. of ether, and filtered through paper. Thefiltrate was washed twice with 300 mls. of 5 wt. percent aqueous sodiumcarbonate and the resultant solution was dried over sodium sulfate andstripped to 93C. under a reduced pressure of 0.125 mm Hg. The residualsolid weighed 19 grams representing a yield of 57 wt. percent. Analysisfound it to be a 2-amino-5-6- dodecyldithio-1,3,4-thiadiazole having anelemental analysis of 9.7 (calc. 12.6) wt. percent nitrogen 26.2

EXAMPLE IV This example illustrates the preparation of still anotherspecies of the product of the invention.

A solution of0.56 gram (0.01 mole) of potassium hydroxide in 25 mls. ofanhydrous ethanol was added toZ-(ethylamino)-5-mercapto-l,3,4-thiadiazole in 100 mls. of diethyleneglycol dimethyl ether at C. under a nitrogen blanket. To the resultantmixture 15 mls. of benzene was added and the mixture was heated at 49C.on a rotary evaporator to remove ethanol, benzene and water leavingresidual solution of potassium salt of2-(ethylamino)-5-mercapto-1,3,4-thiadiazole.

A t-octyl sulfenyl bromide-carbon tetrachloride solution was prepared byadding 1.76 grams (0.11 mole) bromine to a solution of 1.61 grams (0.1 1mole) t-octyl mercaptan and 50 mls. carbon tetrachloride solution at 10dropwise. The resultant mixture was stirred with nitrogen blowing fortwo hours at about 0C.

The t-octyl sulfenyl bromide solution was added to the aforeformedresidual solution at 0C. The resultant product was filtered and strippedto 93C. (0.1 mm Hg). The product was then dissolved in 150 mls. of etherand washed twice with two 150 ml. portions of 5 wt. percent aqueoussodium carbonate and then dried over sodium sulfate. The dried productwas stripped to 93C. (0.1 mm Hg.) leaving a solid residue of 2.3 gramswhich upon analysis was identified as 2-ethylamino-5-toctyldithio-l,3,4-thiadiazole having an elemental analysis of 48 (calc. 47.2) wt.percent carbon, 7.7 (7.5) wt. percent hydrogen, 1 1.4 (13.8) wt. percentnitrogen and 28.2 (31.5) wt. percent sulfur.

EXAMPLE V This example further illustrates the preparation of stillanother species of the product of the invention.

A solution of 28.05 (0.5 )grams of potassium hydroxide in 200 mls. ofethanol was combined with 60 grams (0.45 mole) of2-amino-5-mercapto-l,3,4-thiadiazole in 500 mls. of diethylene glycoldimethyl other at 0C. There was then added 200 mls. of benzene and themixture was then stripped to 92C. on a rotary evaporator removing 310mls. of solvent leaving as residue the potassium salt of2-amino-5-mercapto-l,3,4-thiadiazole.

A t-octyl sulfenyl bromide solution prepared by adding 80 grams (0.5mole) bromine to 73 grams (0.50 mole) t-octyl mercaptan in 500 mls.carbon tetrachloride while blowing with nitrogen at about 0C. followedby passage of nitrogen through the solution vigorously for 2 hours wasadded at C. to the potassium salt residue. The resultant mixture wasstirred at ambient temperature for 1 hour and then filtered. The solidswere washed with ether and the combined organic phase was stripped to93C. on a rotary evaporator. There was recovered as residue 91.5 gramsof a solidliquid mixture. The product was dissolved in 500 mls. of etherand washed with two 500 ml. portions of 5 wt. percent aqueous sodiumcarbonate. The washed product was dried over magnesium sulfate.Additional solids formed. The solids were removed and 200 mls. ofpentane were added to the solution. The resultant solution was filteredand stripped to 93C. (rotary evaporator) and the resultant product wassolid. Analysis determined it to be 2-amino-5-t-octyldithio-1,3,4-thiadiazole having an elemental analysis of 14.8 (15.2)

wt. percent nitrogen and 34.4 (34.6) wt. percent sulfur.

EXAMPLE VI This example illustrates the lubricating oil compositionscontaining the amino hydrocarbyldithio thiadiazole product and theeffectiveness of the amino hydrocarbyldithio thiadiazoles as coppercorrosion inhibitors in said compositions.

The following is a description of the base oil formula tions to whichthe amino hydrocarbyldithio thiadiazole products prepared in thepreceding examples are added in varying amounts and to which comparativeinhibitor components are added. The resultant formulations are subjectedto the ASTM Copper Strip Corrosion Test (D 130-56). Briefly, this testComprises placing a polished copper strip in the test oil compositionfor a 3 hour period at 250F. whereupon the degree of corrosive attackupon the strip is measured using a rating ranging from 1A to 4C with therating of 1A representing the least corrosive attack and the rating of4C representing the greatest corrosive attack.

In following Table l is a description of the base oil formulations:

TABLE 1 Base Oil Base Oil Ingredients A Paraffinic (1000 SUS at F.) 93.192.5 Ethyloleyl Acid Phosphate 1.0 1 Sodium Sulfide Treated Diiso- 5.0

butylene Polysulfide* Sulfurized Triisobutylene* 5 Terpolymer of but 1,lauryl, 0.2 0.5

stearyl and dimetiiylaminoethyl methacrylates Mixture of2-mercaptobenzothia- 0.5

zole and t-C -C alkylamine Oleylamine 0.2 l Dimethyl SiliconeAntifoamant 100 ppm *Extremc pressure agent corrosive to copper.

Table 11 below contains a description of the representative formulationsof the invention and comparative formulations. Further, the formulationsare compared basis the ASTM Copper Strip Corrosion Test as to theirrelative corrosiveness to copper, that is, the relative effectiveness ofthe copper corrosion inhibiting representative and comparative corrosioninhibiting additives in the hydrocarbon oil formulations.

Commercial lnhibitor.

In the above Table II a comparison of the copper strip ratings ofrepresentative Runs 1, 2, 6, 7 and 8 with control Runs and demonstratethe effectiveness of the amino(hydrocarbyldithio)-thiadiazole productsof the invention in inhibiting corrosion. Further, a comparison ofrepresentative Run Nos. 1, 2, 6, 7 and 8 with comparative Run Nos. 3 and9 demonstrate that the thiadiazole products of the invention have aneffectiveness of essentially the same quality as a widely usedcommercial corrosion inhibitor.

1 claim:

1. A composition comprising a major amount ofa hydrocarbon oil oflubricating viscosity and between about 0.01 and 50 wt. percent of anamino hydrocarbyldithio thiadiazole characterized by the formula:

NN RITI- (HJSSR where R is alkyl, aryl, alkaryl or aralkyl of from 1 tocarbons and R is hydrogen or alkyl, aryl, alkaryl or aralkyl of from 1to 30 carbons.

2. A composition in accordance with claim 1 wherein said aminohydrocarbyldithio thiadiazole product is present in an amount of betweenabout 0.01 and 10 wt. percent.

3. A composition in accordance with claim 1 wherein said thiadiazoleproduct is present in an amount of between about 10 and 50 wt. percent.

4. A composition in accordance with claim 2 wherein R is t-dodecyl and Ris hydrogen.

5. A composition in accordance with claim 2 wherein R is t-octyl and Ris hydrogen.

6. A composition in accordance with claim 2 wherein R is t-octyl and Ris ethyl.

7. A composition in accordance with claim 3 wherein R is t-dodecyl and Ris hydrogen.

8. A composition in accordance with claim 3 wherein R is t-octyl and Ris hydrogen.

9. A composition in accordance with claim 3 wherein R is t-octyl and Ris ethyl.

1. A COMPOSITION COMPRISING A MAJOR AMOUNT OF A HYDROCARBON OIL OFLUBRICATING VISCOSITY AND BETWEEN ABOUT 0.01 AND 50 WT. PERCENT OF ANAMINO HYDROCARBYLDITHIO THIADIAZOLE CHARACTERIZED BY THE FORMULA:
 2. Acomposition in accordance with claim 1 wherein said aminohydrocarbyldithio thiadiazole product is present in an amount of betweenabout 0.01 and 10 wt. percent.
 3. A composition in accordance with claim1 wherein said thiadiazole product is present in an amount of betweenabout 10 and 50 wt. percent.
 4. A composition in accordance with claim 2wherein R is t-dodecyl and R'' is hydrogen.
 5. A composition inaccordance with claim 2 wherein R is t-octyl and R'' is hydrogen.
 6. Acomposition in accordance with claim 2 wherein R is t-octyl and R'' isethyl.
 7. A composition in accordance with claim 3 wherein R ist-dodecyl and R'' is hydrogen.
 8. A composition in accordance with claim3 wherein R is t-octyl and R'' is hydrogen.
 9. A composition inaccordance with claim 3 wherein R is t-octyl and R'' is ethyl.